+++ /dev/null
-import "Prelude"\r
-\r
-a :: [Either Integer Integer]\r
-a = [Left 1, Right 2, Left 3, Right 4]\r
-\r
-lefts :: [Either a b] -> [a]\r
-lefts l = [x | Left x <- l] \r
-\r
-main :: [Integer]\r
-main = lefts a\r
---\r
-[1, 3]
\ No newline at end of file